The present invention relates to a descaler for use in iron works for descaling, i.e. removal of oxide film called scale formed on the surfaces of billets, slabs and steel sheets (referred to merely as "steel billet", hereinafter), conducted as a pretreatment in advance of a hot or cold rolling process.
The removal of the scale from the surfaces of steel billets in the hot state hitherto has been made mainly by use of a jet of pressurized water. This method, however, is not preferred partly because of an insufficient descaling effect and partly because of necessity for large electric power in pressurizing the water and uneconomically large energy consumption in the rolling due to excessive cooling of the material by the application of the water jet.
In order to obviate this problem, a rotary-brush type descaling apparatus has been proposed, having a rotary brush composed of a multiplicity of steel wires attached to the surface of a rotary drum. This descaling apparatus, however, cannot be applied satisfactorily to the surface of the steel billet because the steel wires, which are independently fixed to the drum surface, are easily flexed and thus fail to impart a sufficiently large impact to the steel billet surface. In addition, the steel wires are liable to be broken during operation, making the apparatus unusable in an impractically short period of time.
Under this circumstance, there is an increasing demand in the field of industry involved, for the development of a descaler having a sufficient descaling effect and durability and capable of performing the descaling economically with reduced labor.